It turns out Sebastian Blood's (Kevin Alejandro) quest to make super soldiers is under the direction of Slade Wilson (Manu Bennett). Sporting his infamous eye patch, Slade was seen in present-day Starling City, telling Brother Blood that he is determined to burn the vigilante's world to the ground. Why does he hate Oliver (Stephen Amell) so much after spending all that time with him on the island? Because, given a choice, Oliver instinctively saved Sara (Caity Lotz) over Shado (Celina Jade) on the island, much to the dismay of Slade, who had harbored feelings for Shado.

But that was the least of the action during Wednesday's midseason finale, which also featured Barry Allen (Grant Gustin) taking one giant leap to becoming the superhero we all know and love. What's next for him and the rest of Team Arrow? Executive producers Andrew Kreisberg and Greg Berlanti were on hand during a screening of the episode to tease what's next:

Slade Wilson has an axe to grind! Sure, Brother Blood has been trying to create super soldiers, but he's been doing so with the use of Slade Wilson's blood. That's right, Slade is alive and determined take Oliver down for his part in Shado's death. "Oliver and Shado had a relationship, and then really seeing that Slade kind of loved her from afar, and you see what happened to her, so that really is his motivation," Kreisberg said. "He blames Oliver for what happened and what's interesting for our hero is that Oliver blamed himself, too." Berlanti added that the driving force of the second half of the season will be whether they come face-to-face in the present, but their flashbacks will still be fraught with tension. "Things don't get better between them on the island," Berlanti said.

Barry Allen is getting flashy! Upon his return to Central City, Barry Allen was stuck by lightning and thrown into a hodgepodge of different chemicals — in other words, he has become the Flash! With Episode 20 no longer serving as a backdoor pilot, the actual pilot will see the introduction of the Flash's suit. "Barry's love of the hero is going to play a part in the creation of his persona," Kreisberg said. Still, Barry Allen's presence will be felt for the rest of Season 2 on Arrow. "In the back half of the year, you hear about what happened to him in the way that you're hearing now about Star Labs and things like that, in the periphery and certainly in terms of Felicity since she has a connection with him," Berlanti said.

Roy Harper is getting stronger!Roy (Colton Haynes) has finally bitten off more than he can chew. Digging into the truth about Sebastian's blood drive, Roy found himself in the clutches of Brother Blood, who injected Roy with Mirakuru serum before Oliver could save him. "In [the midseason finale], we'll have seen Slade injected and we obviously got a glimpse that he's taken a very dark path," Kreisberg said. "What's fun for us as writers is we see what Roy's potential is to go down that dark path, too. One of the things you'll find out as you go along is it's a deep-seeded anger inside of you that lets you survive the Mirakuru transformation. It's something Slade had, which is why he lived and it's why Roy lived too. One of the fun things that will be happening in the back half of the year is his relationship with the Arrow and how that changes and how the Arrow basically makes it his mission to not let Roy go down the Slade path."

Tommy's purpose revealed!Three ghosts — Shado, Slade and Tommy (Colin Donnell) — appeared to Oliver, each with their own message to help or hurt him along the way. The producers toyed with different ideas for which people would appear, including the possibility of having Oliver's father, Robert Queen (Jamey Sheridan), be one of them. But ultimately, it made sense to have Tommy convey the wisdom needed to get Oliver back on his feet. "So much of the season is based on that character and his loss," Kreisberg said. "It really fit with the season's arc of Oliver's journey of going from vigilante to hero and the person that he feels like he failed. For Tommy to forgive him and tell him to get up and fight, just even talking about it, I get chills." Kreisberg said there is always a chance to see Tommy make another appearance on the show via flashback.

The Arrow has a new mask! "A lot of conversation went into that eight inches of material," Berlanti said of the new mask that Barry Allen bestowed on Oliver after leaving Starling City. Kreisberg added that they debated Oliver having a mask as far back as the pilot of the series, but it felt too cartoonish. "It also fit in with his character that he wasn't someone who ever thought he would be interacting with people," Kreisberg said. "He thought he was going to be this dark sniper firing arrows from the shadows. As the series has progressed and he stepped more and more into the light ... he's really needed that. It seemed perfect in this season that he'd need it and that Barry is the one that ultimately makes it for him."

What did you think of the midseason finale? Were you shocked that Slade was behind everything? Hit the comments!

Arrow returns Wednesday, Jan. 15 at 8/7 c on The CW.

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